Re: [Intel-gfx] [PATCH] drm/i915: fix DP AUX errors due to false timeouts when using wait_event_timeout

2013-05-02 Thread Imre Deak
On Thu, 2013-05-02 at 11:33 +0200, Daniel Vetter wrote: > On Thu, May 2, 2013 at 11:31 AM, Daniel Vetter wrote: > > On Thu, May 2, 2013 at 11:17 AM, Chris Wilson > > wrote: > >> On Thu, May 02, 2013 at 12:00:03PM +0300, Imre Deak wrote: > >>> Due to possible scheduling latencies wait_event_timeo

Re: [Intel-gfx] [PATCH] drm/i915: fix DP AUX errors due to false timeouts when using wait_event_timeout

2013-05-02 Thread Imre Deak
On Thu, 2013-05-02 at 10:17 +0100, Chris Wilson wrote: > On Thu, May 02, 2013 at 12:00:03PM +0300, Imre Deak wrote: > > Due to possible scheduling latencies wait_event_timeout doesn't > > guarantee a non-zero return value, even if the condition becomes true > > before the specified timeout expires.

Re: [Intel-gfx] [PATCH] drm/i915: fix DP AUX errors due to false timeouts when using wait_event_timeout

2013-05-02 Thread Daniel Vetter
On Thu, May 2, 2013 at 11:31 AM, Daniel Vetter wrote: > On Thu, May 2, 2013 at 11:17 AM, Chris Wilson > wrote: >> On Thu, May 02, 2013 at 12:00:03PM +0300, Imre Deak wrote: >>> Due to possible scheduling latencies wait_event_timeout doesn't >>> guarantee a non-zero return value, even if the cond

Re: [Intel-gfx] [PATCH] drm/i915: fix DP AUX errors due to false timeouts when using wait_event_timeout

2013-05-02 Thread Daniel Vetter
On Thu, May 2, 2013 at 11:17 AM, Chris Wilson wrote: > On Thu, May 02, 2013 at 12:00:03PM +0300, Imre Deak wrote: >> Due to possible scheduling latencies wait_event_timeout doesn't >> guarantee a non-zero return value, even if the condition becomes true >> before the specified timeout expires. Thu

Re: [Intel-gfx] [PATCH] drm/i915: fix DP AUX errors due to false timeouts when using wait_event_timeout

2013-05-02 Thread Chris Wilson
On Thu, May 02, 2013 at 12:00:03PM +0300, Imre Deak wrote: > Due to possible scheduling latencies wait_event_timeout doesn't > guarantee a non-zero return value, even if the condition becomes true > before the specified timeout expires. Thus we can incorrectly signal a > timeout and abort a DP AUX

[Intel-gfx] [PATCH] drm/i915: fix DP AUX errors due to false timeouts when using wait_event_timeout

2013-05-02 Thread Imre Deak
Due to possible scheduling latencies wait_event_timeout doesn't guarantee a non-zero return value, even if the condition becomes true before the specified timeout expires. Thus we can incorrectly signal a timeout and abort a DP AUX transaction. If wait_event_timeout returns 0, it's guaranteed that